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991.
Knowledge based methods using Geographic Information System and Remote Sensing for land cover classification and future land allocation in Cyprus are presented. Land cover was categorized combining statistical classification and expert rules, using multi-temporal Landsat TM and MSS data, and digitized maps of elevation and geology. Land needed for future infrastructure was allocated using multi-criteria evaluation. Reforestation area were identified for Pinus brutia and P. nigra comparing expert rules and multi-criteria evaluation.  相似文献   
992.
The exact area calculation of irregularly distributed data is in the focus of all territorial geochemical balancing methods or definition of protection zones. Especially in the deep-sea environment the interpolation of measurements into surfaces represents an important gain of information, because of cost- and time-intensive data acquisition. The geostatistical interpolation method indicator kriging therefore is applied for an accurate mapping of the spatial distribution of benthic communities following a categorical classification scheme at the deep-sea submarine Håkon Mosby Mud Volcano. Georeferenced video mosaics were obtained during several dives by the Remotely Operated Vehicle Victor6000 in a water depth of 1260 m. Mud volcanoes are considered as significant source locations for methane indicated by unique chemoautotrophic communities as Beggiatoa mats and pogonophoran tube worms. For the detection and quantification of their spatial distribution 2840 georeferenced video mosaics were analysed by visual inspection. Polygons, digitised on the georeferenced images within a GIS, build the data basis for geostatistically interpolated mono-parametric surface maps. Indicator kriging is applied to the centroids of the polygons calculating surface maps. The quality assessment of the surface maps is conducted by leave-one-out cross-validation evaluating the fit of the indicator kriging variograms by using statistical mean values. Furthermore, the estimate was evaluated by a validation dataset of the visual inspection of 530 video mosaics not included within the interpolation, thus, proving the interpolated surfaces independently. With regard to both validating mechanisms, we attained satisfying results and we provided each category applied for the identification of biogeochemical habitats with a percentage probability value of occurrence.  相似文献   
993.
Military uses of ocean space consist of both movement rights and operational rights. Only movement rights, which include all rights associated with the mobility of seaborne forces, were codified in the LOS Convention. Operational rights, on the other hand, are primarily customary rights that are governed by the regime of freedom of the seas and defended by the naval power of the United States. This article begins by examining freedom of the seas as a principle of international law, as a bundle of user rights, and as a doctrine. It next examines the major challenges to freedom of the seas in terms of a construct called controlled access. After summarizing the major historical elements of controlled access, the article closes with a brief analysis of the threats to freedom of the seas for military purposes that are posed by multipolarity, the shift in U.S. naval strategy from the open seas to the coastal littorals, and in the withering away of U.S. naval superiority. The major arguments advanced throughout the article are that military uses of ocean space are hegemonic in nature, that their preservation depends on clear maritime superiority, and that they will come under increasing challenge and restriction as the balance of power at sea shifts from unipolarity to multipolarity by the middle of the new millennium.  相似文献   
994.
The living cell is an ever changing, responsive, and adaptive environment where proteins play key roles in all processes and functions. While the scientific community focused for a long time on the decoding of the information required for protein synthesis, little attention was paid to the mechanisms by which proteins are removed from the cell. We now realize that the timely and proper activity of proteins is regulated to a large extent by their degradation; that cellular coping with different physiological cues and stress conditions depends on different catabolic pathways; and that many pathological states result from improper protein breakdown.There are two major protein degradation systems in all eukaryotic cells—the ubiquitin- proteasome and the autophagy-lysosome. The two systems are highly regulated, and—via degradation of a broad array of proteins—are responsible for maintenance of protein homeostasis and adaptation to environmental changes. Each is comprised of numerous components responsible for its coordinated function, and together they encompass a considerable fraction of the entire genome.In this review, we shall discuss the common and diverse characteristics of the ubiquitin-proteasome system (UPS) and autophagy—their substructure, mechanisms of action, function and concerted regulation under varying pathophysiological conditions.  相似文献   
995.
ABSTRACT

The objective of the present study was to validate the accuracy of algorithms, implemented in the currently available RumiWatch Converter (RWC) version V0.7.4.5 of the RumiWatch System (RWS), for the classification of behavioural characteristics from jaw and head movements which are monitored by a noseband halter comprising a pressure sensor and a triaxial accelerometer. The accurate classification of behavioural characteristics in different time resolutions is critical for the usage of the RWS for scientific and practical purposes as chewing behaviour provides essential indicators for the assessment of diet adequacy in dairy cows. To validate the RWC V0.7.4.5 classification accuracy for behavioural characteristics of rumination, eating, drinking, other activity and ruminating chews per bolus by direct observation as reference method, 14 dairy cows participated in the trial. Concordance between the consolidated 1-min and 1-h classification results was assessed. The RWC V0.7.4.5 classified only rumination and ruminating chews per bolus precisely, whereas an algorithm optimisation for the classification of eating, drinking and other activity is required. Additionally, classification results from the 1-min and 1-h time summaries were not in agreement with each other except for rumination.  相似文献   
996.
Using the Global Positioning System (GPS), a ship knows its position continuously to within a few meters anywhere in the ocean. Small, lightweight, relatively inexpensive instruments calculate the ship's position from signals of passing GPS satellites. Oceanographers now attach GPS receivers to floating instruments. These floating buoys broadcast their positions and other data to passing communication satellites, which in turn transmit that information to shore stations. Clearly, a similar locator device (LD) could be placed aboard a ship and its position tracked continuously from shore. We suggest that under the U.N. Law of the Sea Treaty, coastal states can require activated LDs on all ships, including war ships, traversing its territorial sea, archipelagic sea lanes, and straits used for international passage. We further suggest states can require many classes of ships to carry activated LDs while traversing their exclusive economic zones or working above their continental shelf.  相似文献   
997.
Current knowledge of sensory processing in the mammalian auditory system is mainly derived from electrophysiological studies in a variety of animal models, including monkeys, ferrets, bats, rodents, and cats. In order to draw suitable parallels between human and animal models of auditory function, it is important to establish a bridge between human functional imaging studies and animal electrophysiological studies. Functional magnetic resonance imaging (fMRI) is an established, minimally invasive method of measuring broad patterns of hemodynamic activity across different regions of the cerebral cortex. This technique is widely used to probe sensory function in the human brain, is a useful tool in linking studies of auditory processing in both humans and animals and has been successfully used to investigate auditory function in monkeys and rodents. The following protocol describes an experimental procedure for investigating auditory function in anesthetized adult cats by measuring stimulus-evoked hemodynamic changes in auditory cortex using fMRI. This method facilitates comparison of the hemodynamic responses across different models of auditory function thus leading to a better understanding of species-independent features of the mammalian auditory cortex.  相似文献   
998.
Modeling of isometric contractions, due to motor unit (MU) stimulations of Peroneus digiti quarti and peroneus brevis rat muscles, is presented. The modeling is realized through a multimodel, which allows distinguishing asymmetric contractions and relaxation mechanisms for time domain identification. First, this paper compares two fractional functions and a rational transfer function that model each phase of IIA and IIB MU twitch. The advantages of using fractional functions are underlined, since the number of parameters are minimized. Indeed, fractional models, due to its infinite dimension nature, are particularly adapted not only to model complex systems with few parameters but also to obtain a real time exploitable model for a salamander robot simulator. Finally, muscle response for 10 Hz pulse stimulation shows non-stationary characteristics. A method, modeling the transient state of muscle responses and introducing time varying parameters, is presented.  相似文献   
999.
1000.
The Convention on Biological Diversity's strategic plan lays out five goals: “(A) address the underlying causes of biodiversity loss by mainstreaming biodiversity across government and society; (B) reduce the direct pressures on biodiversity and promote sustainable use; (C) improve the status of biodiversity by safeguarding ecosystems, species and genetic diversity; (D) enhance the benefits to all from biodiversity and ecosystem services; (E) enhance implementation through participatory planning, knowledge management and capacity building.” To meet and inform on the progress towards these goals, a globally coordinated approach is needed for biodiversity monitoring that is linked to environmental data and covers all biogeographic regions. During a series of workshops and expert discussions, we identified nine requirements that we believe are necessary for developing and implementing such a global terrestrial species monitoring program. The program needs to design and implement an integrated information chain from monitoring to policy reporting, to create and implement minimal data standards and common monitoring protocols to be able to inform Essential Biodiversity Variables (EBVs), and to develop and optimize semantics and ontologies for data interoperability and modelling. In order to achieve this, the program needs to coordinate diverse but complementary local nodes and partnerships. In addition, capacities need to be built for technical tasks, and new monitoring technologies need to be integrated. Finally, a global monitoring program needs to facilitate and secure funding for the collection of long-term data and to detect and fill gaps in under-observed regions and taxa. The accomplishment of these nine requirements is essential in order to ensure data is comprehensive, to develop robust models, and to monitor biodiversity trends over large scales. A global terrestrial species monitoring program will enable researchers and policymakers to better understand the status and trends of biodiversity.  相似文献   
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